Electricity: circuit makers and breakers – Electric switch details – Actuators
Reexamination Certificate
2003-08-01
2004-11-02
Friedhofer, Michael A. (Department: 2832)
Electricity: circuit makers and breakers
Electric switch details
Actuators
C200S200000, C200S553000, C200S439000
Reexamination Certificate
active
06812419
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a three-position enable switch which sequentially switches a contact mechanism of its own from an OFF state to an ON state and again to the OFF state according to the position of a manipulation member in a specific direction of its operation. More particularly, the invention is concerned with an enable switch suited for a portable operator panel used for teaching an industrial robot, for example.
BACKGROUND ART
Conventionally, there exist commercially available three-position enable switches which permit a manipulation member to sequentially stop at a non-operated position, an intermediate stop position and a fully operated position as operated in a particular direction of operation with a finger of the hand, wherein a contact mechanism is set to an OFF state when the manipulation member is not operated and held at the non-operated position, the contact mechanism is set to an ON state when the manipulation member is operated up to the intermediate stop position, and the contact mechanism is again set to the OFF state when the manipulation member is further operated up to the fully operated position. The enable switches of this kind are provided on a portable operator panel used for teaching an industrial robot, for example, to ensure operator safety.
Specifically, a portable operator panel
401
connected to a control apparatus for controlling a robot is provided with enable switches
411
a,
411
b
together with manipulation switches
409
a,
409
b,
etc. corresponding to various motions of the robot, as shown in
FIGS. 5 and 6
. Operation of the individual manipulation switches
409
a,
409
b,
etc. is enabled when the enable switches
411
a,
411
b
are under conditions where their manipulation members have been operated to the intermediate stop position, that is, when contact mechanisms of the enable switches
411
a,
411
b
are in the ON state. On the other hand, operation of the individual manipulation switches, etc. is disabled when the enable switches
411
a,
411
b
are under conditions where their manipulation members are at the non-operated or fully operated position, that is, when the contact mechanisms of the enable switches
411
a,
411
b
are in the OFF state.
With this arrangement, if the robot makes a motion unintended by the operator due to misoperation of a manipulation switch, for instance, when the operator is setting the robot into motion by manipulating the manipulation switch while operating the manipulation member of an enable switch, it is possible to set the contact mechanism of the enable switch to the OFF state and instantly stop the motion of the robot regardless of the operating state of the manipulation switch by letting the finger of the hand away from the manipulation member of the enable switch or by tightly pressing the manipulation member further from the intermediate stop position to the fully operated position.
When operating a portable operator panel, the operator normally holds it from its side with its front side on which the manipulation switches, etc. are arranged oriented frontward so that the operator can easily observe the manipulation switches, etc. with the eyes. Particularly when operating a large-sized portable operator panel, the operator holds it from both sides. To operate the robot through the portable operator panel, the operator has to operate not only the manipulation switches, etc. as stated above but also the enable switches at the same time while holding the portable operator panel.
Thus, taking into consideration the operability of the portable operator panel, the enable switches should be arranged on the portable operator panel in such a manner that its manipulation members are located in an area where fingers of the operator's hand holding the portable operator panel can be positioned face to face with the manipulation members. If the manipulation members are so arranged, the operator can press the manipulation members of the enable switches by using his or her fingers placed face to face with the manipulation members from the rear side of the panel among the fingers holding the portable operator panel from its side.
In the conventional enable switch, however, the manipulation member is provided in such a manner that it shifts generally along a straight line connecting the non-operated position to the fully operated position via the intermediate stop position, and a surface of the manipulation member with which a finger of the hand comes into contact moves in a position generally parallel to the panel surface when the manipulation member is depressed. For this reason, movement of the surface of the manipulation member with which the finger of the hand is in contact does not conform to the swing motion of the finger about its joint produced when the finger facing the manipulation member presses the manipulation member with the hand holding the portable operator panel from its side. Therefore, operability of the manipulation member is poor, and this makes it impossible in certain cases to exactly move the manipulation member in the event of an emergency stop which requires an immediate action to be taken. Also, to smoothly move the manipulation member of the conventional enable switch along the straight line over a relatively large stroke from the non-operated position to the fully operated position via the intermediate stop position, it is inevitable to make some clearance between outside surfaces of the manipulation member and a guide member in a direction perpendicular to its moving direction. For this reason, the manipulation member tends to be inclined with respect to its moving direction. As a consequence, if multiple contact mechanisms are provided to achieve enhanced safety, there might arise a case where ON/OFF states of the multiple contact mechanisms could not be switched at the same time by a single manipulation member.
Furthermore, there exist no conventional enable switches which have been designed with ease of installation on a portable operator panel in mind. Thus, it has not been possible to easily install the conventional enable switches produced as separate components, resulting in a problem that the conventional enable switches would make the process of manufacturing the portable operator panel rather complex.
Accordingly, it is an object of the invention to provide an enable switch which makes it possible to exactly move a manipulation member with improved operability in the event of an emergency stop which requires an immediate action by adapting the movement of a surface of the manipulation member in contact with a finger of the hand holding a portable operator panel from its side, for instance, to the motion of the finger facing the rear side of the panel, achieve an improvement in safety by providing multiple contact mechanisms in such a manner that the ON/OFF states of the multiple contact mechanisms can be switched at the same time by moving a single manipulation member, and simplify the process of manufacturing the portable operator panel by making it possible to easily install the enable switch produced as a separate component on the portable operator panel.
DISCLOSURE OF THE INVENTION
The present invention employs the following constructions as means for solving the aforementioned problems.
According to the present invention, an enable switch provided with a contact mechanism having a movable contact which is biased toward an OFF state switches the contact mechanism between its ON and OFF states during a period when a manipulation member moves from a non-operated position to an intermediate stop position and during a period when the manipulation member moves from the intermediate stop position to a fully operated position. The enable switch is characterized in that it is provided with a motion transmission mechanism including a first elastic member of which one end swingably supports the manipulation member in a housing and biases the manipulation member toward the non-operated position in such a manner that part of the manipulation
Fukui Takao
Miyauchi Kenji
Nobuhiro Masaki
Friedhofer Michael A.
Idec Izumi Corporation
LandOfFree
Enable switch does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Enable switch, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Enable switch will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3325941